Difluoramination of Heterocyclic Ketones: Control of Microbasicity
摘要:
Difluoramination of a tetrahydro-1,5-diazocine-3,7(2H, 6H)-dione to the corresponding 3,3,7,7-tetrakis(difluoramino)diazocine was achieved by a judicious choice of protecting group. Arenesulfonyl protecting groups for the diazocine nitrogens proved superior to acetyl during the slow disruption of the transannular bridge in 9-oxa-3,7-diazabicyclo[3.3.1]nonane intermediates by difluorosulfamic acid, While a 1,5-ditosyl derivative failed to proceed beyond the product of addition of difluoramine to one ketone carbonyl (hemiaminal 6), the use of 4-nitrobenzenesulfonyl as the protecting groups lowered the nitrogens' basicities below that of the oxygen site in the dione and intermediates, allowing the reaction to proceed to a gem-bis(difluoramino)diazocine product (11). A safer procedure for handling difluoramine is described.
Facile Preparation of 3,7-Diazabicyclo[3.3.0]octane and 3,7,10-Triheterocyclic [3.3.3]Propellane Ring Systems from 1,5-Diazacyclooctane 3,7-Derivatives<sup>1</sup>
作者:Paritosh R. Dave、Farhad Forohar、Theodore Axenrod、Kajal K. Das、Lida Qi、Clara Watnick、Hamid Yazdekhasti
DOI:10.1021/jo9614755
日期:1996.1.1
5-dinitro-3,7-diazabicyclo[3.3.0]octane, (12). Acid-catalyzed hydration of 1a, in contrast, gives the expected 5-methyl-3,7-diazabicyclo[3.3.1]nonan-1-ol (10). Reaction of the dibromide 8 with the nucleophiles, sodium sulfide, sodium oxide, and sodium p-toluenesulfonamide conveniently delivers the corresponding novel 3,7,10-triheterocyclic [3.3.3]propellanes.
Synthesis of 1,3,3-Trinitroazetidine via the Oxidative Nitrolysis of N-p-Tosyl-3-azetidinone Oxime
作者:T. Axenrod、C. Watnick、H. Yazdekhasti、P. R. Dave
DOI:10.1021/jo00112a014
日期:1995.4
The tert-butyldimethylsilyl ether of 1,3-dibromo-2-propanol reacted with p-toluenesulfonamide in the presence of K2CO3 to give the corresponding N-p-tosyl-3-azetidinol. The same azetidinol was obtained when the similarly silyl-protected 3-(p-toluenesulfonamido)propan-2-ol 1-(p-toluene-sulfonate) was treated with LiH. Desilylation and oxidation of the N-p-tosyl-3-azetidinol followed by oximation readily afforded N-p-tosyl-3-azetidinone oxime. Oxidative nitrolysis of the latter intermediate delivered 1,3,3-trinitroazetidine through a new sequence of reactions.